In a couple of instances we’ve seen in the rules that state that you can use a skill to modify another skill. I think the main one that we’ve seen so far is inhuman strength. It says something about you can use might to modify another skill, or something like that.

What does this mean, how does it work, and how does it work with inhuman speed specifically?

2 Answers
2

See page 213 of Dresden Files: Your Story or Combining Skills in the Spirit of the Century SRD

A skill modifies another when a character does something (with the primary skill) in a situation where another (secondary) skill could (or must) help or hinder. This often occurs when doing two things at once.

The character rolls the primary skill with a bonus of +1 if the secondary skill is higher than the primary skill or a penalty of -1 if it is lower. If they are equal there is no modifier.

The bonus or penalty is waived if the secondary skill can only help or hinder.

For example: If Alice needs to throw a knife (Weapons) while balancing on a spinning log (Athletics) then she must roll Weapons, but throwing the knife accurately is harder because she is balancing. If her Athletics is equal to or higher than her Weapons then she can cope without a problem, but if it isn't as good then she gets a -1 penalty to her Weapons.

Another example, using Might, would be a wrestling match. This is hand to hand combat and uses the Fists skill, but strength is more important than usual so Might would modify each participant's Fists.

The terms seem to have been dropped in Dresden, but in SotC they were described as restricting or complimenting the skill if either a bonus or penalty were impossible.

One of the features of Inhuman Might is that it means a character is considered to always have a Might score that is higher than every other skill for the purposes of calculating this modifier. This isn't a generic feature of supernatural powers that you can apply to Inhuman Speed, it is a specific rule for that specific power. (That said, Inhuman Speed has a specific power that lets you ignore the penalty for taking a supplemental action when moving one zone)

In addition to the excellent answer by Coreworlder, there is the core FATE game mechanic of maneuvers. Simply put, you can do a maneuver using Might to place an aspect on your character, and tag that new aspect for free to gain a +2 to a subsequent skill use.

This has one benefit. It forces you to describe how the first skill helps the second, because you have to name your aspect and it has to make sense when you are tagging it.

For example, you may maneuver using might and place the aspect Brace for impact on yourself. Then you can tag that aspect and get a +2 on your athletics roll to jump off a building and land safely.